Cakradatta (Cikitsasangraha) 1.8

1.8

prāṇāvirodhinā cainaṃ laṅghanenopapādayet .
balādhiṣṭhānamārogyaṃ yadartho'yaṃ kriyākramaḥ .. 8 ..

And one should treat him with fasting that does not conflict with the vital breath; / health has its basis in strength, and that is the purpose for which this procedure of treatment exists. (8)